Physiological relationships between dwarf mistletoe and ponderosa pine

Graduation date: 1964A comparative study was made of Pinus ponderosa Laws, and\ud Arceuthobium campylopodum Engelm. f . campylopodum to determine\ud (1) whether or not the parasite or parasitized tissues accumulate\ud abnormal concentrations of minerals, (2) whether or not there\ud was evidence of a blockage of mineral translocation in the phloem\ud because of the parasite, and (3) whether or not changes occurred in\ud host foliage which could be interpreted as mineral deficiency.\ud Also, comparative analyses using chromatographic methods\ud were made of simple carbohydrates and free amino acids. Quantitative\ud analyses of carbohydrates also were carried out. Manometric\ud methods were employed to evaluate the ability of host and parasite\ud to utilize exogenously supplied carbohydrates and amino acids.\ud Substances identified by chromatography in the host and parasite served as substrates in the respiration studies to determine their\ud usability.\ud The results showed the parasite and swollen bark ramified by\ud the parasite to have higher contents of nitrogen, phosphorus, and\ud potassium than bark adjacent to the swellings and sometimes more\ud than the host foliage. Magnesium content was greatest in the parasite.\ud No difference occurred between fusiform swellings and adjacent\ud bark. Calcium was the exception in that it did not accumulate\ud in the parasaite. No evidence was found that mineral translocation\ud was blocked in the phloem except for calcium. Calcium was more\ud abundant below the infection than above. No evidence was found\ud which would substantiate the theory that the parasite caused mineral\ud deficiencies in the host's foliage.\ud Neither was the movement of sugars, as indicated by ouantitative\ud analysis, interrupted by the mistletoe or the swollen bark\ud from which it grew.\ud The host contained raffinose which was not found in the parasite,\ud and the parasite contained an unknown substance, possibly a\ud uronic acid, a methylpentose or a deoxy sugar, which was not found\ud in the host.\ud Dwarf mistletoe aud its host contained virtually the same amino\ud acids, the chief exception being the presence of cysteic acid and the absence of glycine in the parasite.\ud Dwarf mietletoe was found to use a variety of sugars in its\ud metabolism, including those identified from the host. Respiration\ud of pine tigsues was not stimulated by the addition of carbohydrate.\ud Tissues of both host and parasite responded to the addition of amino\ud acid and amides